Performance Of Multiple Pleated Plate-polyurethane Foam Energy Absorption Connector Under Static And Impact Loading

In recent years,economic loss and human injuries caused by various explosions have attracted the attention of scholars at home and abroad on explosion resistance of buildings.In addition to military applications,the explosion resistance design of buildings has also attracted higher attention.In the past,people mainly studied energy absorption structures related to various types of thin-walled metal tubes.However,recently,foam-filled energy absorption structures have gradually entered the field of applications.Polyurethane foam has become a focus of the research community as an energy absorption material due to its low density and strong energy absorption capacity.It is found that polyurethane foam filling of the empty metal tubes can greatly improve the bearing capacity and energy dissipation performance.In this paper,novel energy absorption connectors are proposed.The energy absorption connectors are polyurethane foam-filled with low carbon steel plates at the faces to form composite structures.The connectors can be placed between the explosion-resistant facade and structural members of a building to absorb the explosion energy generated by the blast and reduce the load transferred to the structural members.In order to study the energy dissipation mechanism of the proposed energy absorption connectors,quasi-static and impact load tests were carried out.The validated finite element models were modeled for numerical simulations.Finally,based on the experimental and finite element analyses,the energy absorption indices were analyzed.The salient points of this study are listed below.1.Two sets of polyurethane foam-filled energy absorption connectors with the same parameters were designed and manufactured.The Material Testing System(MTS)was employed to carry out quasi-static load tests of one set of the energy absorption connectors.The influences of the bending angle,folding plate thickness and polyurethane foam on quantitative evaluation of energy absorption indices related to the mechanical properties and energy absorption performances of the energy absorption connectors under quasi-static compression tests were evaluated.The detail investigations of the effects on failure mode,mechanical properties and energy dissipation performance of the energy absorption connectors were performed.2.A drop-hammer impact test system was used to conduct impact tests on another set of energy absorption connectors.The energy absorption indices as in the case of quasistatic compression were evaluated for the impact tests.The failure modes and mechanical properties of the specimens under impact tests along with the comparison of the results of quasi-static and impact tests were studied.3.The finite element models of the energy absorption connectors were modeled.A finite element software,LS-DYNA,was used to simulate the quasi-static and impact tests.The results of the simulations were compared with the experimental ones.The comparison delivered acceptable accuracies of the finite element models.